If we're counting all Blizzard devs then I'd have to say Tigole (Jeff Caplan) and Furor (Alex Afriasbi) who are basically responsible for my WoW addiction (Tigole for annoucing via LoS's blog that he was going to work for Blizzard on their "new MMO" and Furor for effectively ending my EQ career with his "Why wow is better" post on the FoH board ( before he went to work for Blizzard).

Counting actual Blues; GC without a doubt. I always had respect for the man but the MoP beta theorycrafting thread should be a "how to" for MMO developers interacting with their playerbase.

Of the CM's: Zar, its like hearing it from another player and Daxx for just being awesome! :)

I am going to go with Bashiok for a number of reasons - but just mostly as I thik the tone is always quite good, which creates a fair and approachable type of feeling. (Not that we really can approach blues - but it feels that way anyway.)

All the CM's are cool, but yeah, I like Bashiok. A lot of what he says is just his thoughts and opinions as a person and player. He gets a lot of flak for it, and people like to read a lot into what he says, but I think it's cool.